Electric oil pump device

ABSTRACT

A filter module includes an attachment attached to an attachment catch. The attachment of the filter module on the attachment catch of the electric oil pump main body to the attachment catch is fixed in a posture where an outlet port of the filter module is caused to communicate with the suction port of the electric oil pump main body.

CROSS REFERENCE TO RELATED APPLICATION

The present invention claims priority under 35 U.S.C. § 119 to JapaneseApplication No. 2019-000745 filed on Jan. 7, 2019, the entire contentsof which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present disclosure relates to an electric oil pump device.

BACKGROUND

In the related art, an electric oil pump that includes a pump portion, amotor portion that drives the pump portion, a suctioning port thatsuctions oil, and an ejection port that ejects the oil is known.

An electric oil pump disclosed in Japanese Patent Laid-Open No.2017-002841, for example, includes a pump portion, a motor portion, anda suctioning port and an ejection port provided at the pump portion. Theelectric oil pump is mounted in an oil pan of a vehicle in the form inwhich the electric oil pump is dipped in the oil in the oil pan andsuctions the oil directly with the suctioning port at on the pumpportion into the pump portion. The oil in the pump portion is ejectedfrom the ejection port and is then fed to a transmission or the like ofthe vehicle.

Meanwhile, a strainer is known as a filter module for removingimpurities from the oil before being suctioned into an oil pump in therelated art.

A strainer disclosed in Japanese Patent Laid-Open No. 2017-160955, forexample, includes a case portion that accommodates a filtration materialand a long and thin tubular portion that communicates with the caseportion aid and is mounted in an oil pan in the a form in which the caseportion is dipped in the oil in the oil pan. An end of the tubularportion is connected to an oil pump outside the oil pan. The oilsuctioned from a suctioning hole at in the case portion into the caseportion passes through the filtration material in the case portion andthe tubular portion, then flows out of a flowing-out hole at in thetubular portion, and is suctioned into the oil pump.

According to the strainer disclosed in Japanese Patent Laid-Open No.2017-160955, since it is necessary to align the strainer attached to theoil pan and with the suctioning port of the oil pump disposed outsidethe oil pan, and mountability of the oil pump and the strainer to thevehicle may be degraded. In a case in which the strainer is attached tothe oil pan earlier than the strainer, for example, mountability of theoil pump may be degraded. In a case in which the alignment is notsuccessfully performed when the oil pump is attached, a situation inwhich it is necessary to attach the strainer again is also conceivable.In a case in which the oil pump is attached to the outside of the oilpan earlier than the strainer, mountability of the strainer may bedegraded. In a case in which the alignment is not successfully performedwhen the strainer is attached, a situation in which it is necessary toattach the oil pump again is also conceivable.

Also, the strainer disclosed in Japanese Patent Laid-Open No.2017-160955 requires a space for disposing the long and thin tubularportion (pipe) to be provided inside the oil pan, and it is thusdifficult to save a space for the oil pan and to reduce the weight ofthe oil pan. Further, the long and thin tubular portion applies aresistance to the oil flowing in the tubular portion in the strainerdisclosed in Japanese Patent Laid-Open No. 2017-160955, and pumpefficiency may thus be degraded.

As described above, the strainer disclosed in Japanese Patent Laid-OpenNo. 2017-160955 has problems that mountability of the oil pump and thestrainer may be degraded, it may be difficult to save space and toreduce the weight of oil reservoir equipment, such as an oil pan, andpump efficiency may be degraded. Note that similar problems may occureven in a case in which the strainer disclosed in Japanese PatentLaid-Open No. 2017-160955 is connected to an electric oil pump that isnot disposed outside the oil pan but is attached to the inside of theoil pan as in the case of the electric oil pump disclosed in JapanesePatent Laid-Open No. 2017-002841.

SUMMARY

Example embodiments of the present disclosure each provide an electricoil pump device capable of improving mountability of a filter module andan electric oil pump main body, saving a space and reducing the weightof oil reservoir equipment, and improving pump efficiency of theelectric oil pump main body.

According to a first example embodiment of the present disclosure, anelectric oil pump device includes an electric oil pump main bodyincluding a pump, a motor that drives the pump, a suction port thatsuctions oil, and an ejection port that ejects the oil. The electric oilpump device includes a filter module that includes an inlet port thatreceives the oil, an outlet port that discharges the oil passing throughthe inlet port, and an attachment that is attached to the electric oilpump main body, an attachment catch, which is provided at on theelectric oil pump main body, to which the attachment of the filtermodule is attached, and a fastener that secures, to the attachmentcatch, the attachment of the filter module on the attachment catch ofthe electric oil pump main body in a posture in which the outlet port iscaused to communicate with the suction port of the electric oil pumpmain body.

According to the exemplary first disclosure of the present disclosure,excellent effects of improving mountability of the filter module and theelectric oil pump main body, to save space and reduce the weight of theoil reservoir equipment, and to improve pump efficiency of the electricoil pump main body are achieved.

The above and other elements, features, steps, characteristics andadvantages of the present disclosure will become more apparent from thefollowing detailed description of the example embodiments with referenceto the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating an electric oil pump deviceaccording to an example embodiment of the present disclosure.

FIG. 2 is an exploded perspective view illustrating a motor accommodatedinside a housing of the electric oil pump device, a pump cover of apump, and the respective members in the pump cover according to anexample embodiment of the present disclosure.

FIG. 3 is an exploded perspective view illustrating the electric oilpump device from the −Z side.

FIG. 4 is a cut away perspective view illustrating a strainer accordingto an example embodiment of the present disclosure in a partially cutaway state.

FIG. 5 is a plan view illustrating an electric oil pump device accordingto a first example embodiment of the present disclosure from the −Z sidein the Z-axis direction in a state in which an external pipe and afilter module have been removed therefrom.

FIG. 6 is a plan view illustrating the electric oil pump deviceaccording to the first example embodiment from the −Z side in the Z-axisdirection in a state in which the external pipe and the filter modulehave been attached thereto.

FIG. 7 is an exploded side view illustrating an electric oil pump deviceaccording to a second example embodiment of the present disclosure fromthe +Y side.

FIG. 8 is a perspective view illustrating a filter module of an electricoil pump device according to a third example embodiment of the presentdisclosure.

DETAILED DESCRIPTION

Hereinafter, electric oil pump devices according to example embodimentsof the present disclosure will be described with reference to drawings.In the example embodiments, an electric oil pump device that suppliesoil to a transmission mounted in a vehicle, such as a car, will bedescribed. Also, sizes, numbers, and the like of the respectivestructures in the following drawings may be different from those ofactual structures for ease of understanding of the respectiveconstituents.

Also, an XYZ coordinate system will appropriately be illustrated as athree-dimensional orthogonal coordinate system in the drawings. In theXYZ coordinate system, the X-axis direction is defined as a directionthat is parallel to an axial direction of a central axis J illustratedin FIG. 1. The central axis J is a central axial line of a shaft (motorshaft) 13 of a motor portion 10, which will be described later. TheZ-axis direction is defined as a direction that is parallel to a centralaxial line of a suctioning portion (which will be described later) ofthe motor portion 10. The Y-axis direction is defined as a directionthat perpendicularly intersects both the X-axis direction and the Z-axisdirection. In each of the X-axis direction, the Y-axis direction, andthe Z-axis direction, the side to which the arrow is directed in thedrawing is defined as a +side while the opposite side is defined as a−side.

Also, the positive side (+X side) in the X-axis direction will bereferred to as a “rear side” while the negative side (−X side) in theX-axis direction will be referred to as a “front side” in the followingdescription. Note that the rear side and the front side are names usedonly for explanation and do not limit actual positional relationshipsand directions. Also, the direction (X-axis direction) that is parallelto the central axis J will simply be referred to as an “axial direction,the radial direction around the central axis J will simply be referredto as a “radial direction”, and the circumferential direction around thecentral axis J, that is, the circumferential direction (θ direction)around the central axis J will simply be referred to as a“circumferential direction”.

Note that in the specification, extending in the axial direction alsoincludes a case of extending in a direction inclined within a range ofless than 45° with respect to the axial direction in addition to a caseof extending strictly in the axial direction (X-axis direction). Also,extending in the radial direction in the specification also includes acase of extending in a direction inclined within a range of less than45° with respect to the radial direction in addition to a case ofextending strictly in the radial direction, that is, in the directionthat is perpendicular to the axial direction (X-axis direction).

EXAMPLE EMBODIMENTS <Overall Configuration>

FIG. 1 is a perspective view illustrating an electric oil pump device 1according to an example embodiment. The electric oil pump device 1according to the example embodiment includes an electric oil pump mainbody that has a motor portion 10, a housing 14, a pump portion 40, aninverter 100, and a heatsink 120 as illustrated in FIG. 1. Also, theelectric oil pump device 1 includes a filter module 150. The motorportion 10 includes a shaft (which will be described later) disposedalong the central axis J extending in the axial direction.

The pump portion 40 is located on one side (front side) of the motorportion 10 in the axial direction and is driven by the motor portion 10via a shaft 13 to eject oil. The inverter 100 is disposed on the rearside of the motor portion 10 and controls driving of the motor portion10.

The heatsink 120 is secured to an end surface of a case 101 of theinverter 100 on the rear side in the axial direction and cools theinverter 100 by discharging heat generated by an operation thereof anddelivered from the inverter 100. The heatsink 120 includes a pluralityof fins 121 extending in the Z-axis direction in order to efficientlyperform the aforementioned heat discharge.

The housing 14 serves both as a housing of the motor portion 10 and ahousing of the pump portion 40 and includes a partition wall thatpartitions the motor portion 10 from the pump portion 40. The housing 14is made of a cast article made of metal (aluminum, for example).

In the electric oil pump device 1 according to the example embodiment,the housing of the motor portion 10 and the housing of the pump portion40 that are formed by the housing 14 are parts of a single member. Withsuch a configuration, a boundary between the housing of the motorportion 10 and the housing of the pump portion 40 in the axial directionis defined as follows. That is, the center of the partition wall thatpartitions the motor portion 10 and the pump portion 40 in the axialdirection is a boundary between the motor portion 10 and the pumpportion 40 in the axial direction.

<Motor Portion 10>

FIG. 2 is an exploded perspective view illustrating the motor 11accommodated inside the housing (14 in FIG. 1), a pump cover 52 of thepump portion 40, and the respective members in the pump cover 52. Themotor portion 10 includes the motor 11 as illustrated in FIG. 2. Themotor 11 is an inner rotor-type motor, for example, and includes theshaft 13 as a motor shaft and a cylindrical stator 22.

Inside the stator 22 in the radial direction, a rotor which is notillustrated in FIG. 2 is secured to an outer circumferential surface ofthe shaft 13, and an outer circumferential surface of the rotor faces aninner circumferential surface of the stator 22 with a predetermined gaptherebetween. The rotor is secured to the shaft 13 on the rear side inthe axial direction.

The shaft 13 penetrates through a through-hole provided in the partitionwall of the housing (14 in FIG. 1) that partitions the motor portion 10and the pump portion 40 and enters the pump portion 40 from the motorportion 10.

<Pump Portion 40>

The pump portion 40 includes a pump rotor 47 and a pump cover 52.

(Pump Rotor 47)

The pump rotor 47 is attached to an end portion of the shaft 13 on thefront side. The pump rotor 47 includes an inner rotor 47 a and an outerrotor 47 b. The inner rotor 47 a is secured to the shaft 13. The outerrotor 47 b surrounds the outside of the inner rotor 47 a in the radialdirection.

The inner rotor 47 a has an annular shape. The inner rotor 47 a is agear that has teeth on an outer surface thereof in the radial direction.The inner rotor 47 a rotates about the axis (the θ direction in FIG. 1)along with the shaft 13. The outer rotor 47 b has an annular shapesurrounding the outside of the inner rotor 47 a in the radial direction.The outer rotor 47 b is a gear that has teeth on an inner surfacethereof in the radial direction. An outer surface of the outer rotor 47b in the radial direction has a circular shape.

The gear on the outer surface of the inner rotor 47 a in the radialdirection and the gear of the inner surface of the outer rotor 47 b inthe radial direction engage with each other, and the outer rotor 47 brotates by the inner rotor 47 a rotating with rotation of the shaft 13.That is, the pump rotor 47 rotates due to rotation of the shaft 13.

Due to the inner rotor 47 a and the outer rotor 47 b rotating, a volumein the engagement portion between the inner rotor 47 a and the outerrotor 47 b changes. A region in which the volume decreases is apressurization region, and a region in which the volume increases is anegative pressure region.

(Pump Cover 52)

The housing 14 illustrated in FIG. 1 includes an opening at an end onthe front side in the axial direction. The opening is closed with thepump cover 52 illustrated in FIG. 2. The pump cover 52 is secured to thehousing 14 with a bolt 53.

The pump cover 52 accommodates the pump rotor 47 that includes the innerrotor 47 a secured to the shaft 13 and the outer rotor 47 b that isengaged with the inner rotor 47 a.

The rotor accommodation portion that accommodates the pump rotor 47 ofthe pump portion 40 and the motor accommodation portion of the motorportion 10 may be parts of a single member or may be separate elements.Also, the housing of the motor portion 10 and the housing of the pumpportion 40 may be separate elements.

<Inverter 100>

The inverter 100 illustrated in FIG. 1 includes an electronic substratein the case 101. The electronic substrate includes a plurality ofelectronic components and a substrate with the plurality of electroniccomponents mounted thereon. On the substrate, a plurality of bipolartransistors (MOS-FET) as switching elements are mounted. Since theplurality of bipolar transistors generate a large amount of heat withdriving, the temperature of the entire inverter 100 is raised. One ofroles of the heatsink 120 is to discharge heat delivered from theinverter 100, the temperature of which has been raised due to the heatgenerated by the bipolar transistors.

<Filter Module 150>

In FIG. 1, the filter module 150 is secured to an end surface of thehousing 14 on the −Z side in the Z-axis direction. The filter module 150plays a role of filtering oil before being suctioned by the suctioningport, which will be described later, of the pump portion 40.

FIG. 3 is an exploded perspective view illustrating the electric oilpump device 1 from the −Z side. The housing 14 is a part of the electricoil pump main body provided with the motor portion 10, the pump portion40, and the like. The suctioning port 41 through which the oil issuctioned into the pump portion 40 is provided in a region that servesas the housing of the pump portion 40 in the entire region of thehousing 14 in the axial direction. The suctioning-side flange 43 isprovided at an end portion of the region on the −Z side in the Z-axisdirection, and the suctioning port 41 is provided in the suctioning-sideflange 43.

Note that FIGS. 1 and 3 illustrate a state in which an external flange201 has been attached to an ejection-side flange 44 of the electric oilpump device 1 and an external pipe 202 has been connected to theexternal flange 201.

The respective components of the electric oil pump device 1 are designedon the assumption that the electric oil pump device 1 is placed in anoil pan of a transmission or the like in a posture in which thesuctioning port 41 is directed downward in the direction of gravity. Inthe electric oil pump device 1 in the aforementioned posture, the filtermodule 150 is located lower down in the gravity direction.

The ejection-side flange 44 is provided on an end portion of the pumpcover 52 on the −Z side in the Z-axis direction. The ejection port 42that ejects the oil in the pump portion 40 is provided in theejection-side flange 44. The external flange 201 is connected to theejection-side flange 44, and the external pipe 202 is connected to theexternal flange 201. The oil discharged from the ejection port 42 of thepump portion 40 is fed to the transmission and the like of the vehiclevia the external flange 201 and the external pipe 202. The suctioningport 41 is provided so as to be closer to the side of the motor portion10 than the ejection port 42 is in the axial direction.

The base 14 a projecting from the circumferential surface of the housing14 on the −Z side is provided on an end portion of the housing 14 on therear side in the axial direction that is an end on the −Z side in theZ-axial direction. The base 14 a is a part of the motor portion 10.

The filter module 150 is attached to the suctioning-side flange 43 andthe base 14 a. That is, the suctioning-side flange 43 and the base 14 afunction as an attachment catching portion.

An end surface (43 a) of the suctioning-side flange 43 on the −Z side inthe Z-axis direction and an end surface (14 a 1) of the base 14 a on the−Z axis side in the Z-axis direction are attachment catching surfaces towhich the filter module 150 is attached. Hereinafter, the former endsurface and the latter end surface will be referred to as an attachmentcatching surface 43 a and an attachment catching surface 14 a 1,respectively.

The filter module 150 includes an accommodation case 151 that has aplane extending in the axial direction and the Y-axis direction as anouter surface and has a flattened shape with a dimension thinned in theZ-axis direction. An inlet port opening 151 a is provided in an endsurface of the accommodation case 151 on the −Z side in the Z-axisdirection. The inlet port opening 151 a functions as an inlet port ofthe filter module 150.

The electric oil pump device 1 is placed in the oil pan of thetransmission in a posture in which the suctioning port 41 is directeddownward in the gravity direction, and then in the oil pan, the filtermodule 150 of the electric oil pump device 1 is dipped in the oil storedin the oil pan. The inlet port opening 151 a of the filter module 150 isdirected outward in the radial direction and faces a bottom surface ofthe oil pan in the oil pan. Therefore, impurities that have sunk to thebottom of the oil pan are efficiently suctioned into the filter module150 through the inlet port opening 151 a.

FIG. 4 is a cut away perspective view illustrating the filter module 150in a partially cut away state. The cut surface of the filter module 150illustrated in the drawing extends in the X-Z-axis direction at an endportion of the filter module 150 on the +Y side in the Y-axis direction.

A flange portion 151 b projecting on the +Z side from an end surface ofthe filter module 150 on the +Z side in the Z-axis direction is providedon the end surface. A surface of the flange portion 151 b on the +Z sideis an attachment surface 151 b 1 that is attached to the attachmentcatching surface 43 a of the suctioning-side flange 43 on the pumpportion 40 illustrated in FIG. 3. The attachment surface 151 b 1 of thefilter module 150 illustrated in FIG. 4 is provided with an outlet port151, two through-holes 151 d, an O ring 165, and an O ring groove 166.The O ring 165 is inserted into the O ring groove 166 surrounding thecircumference of the outlet port 151 c and projects on the +Z sidebeyond the attachment surface 151 b 1. The O ring 165 seals a gapbetween the attachment surface 151 b and the attachment catching surface43 a of the suctioning-side flange 43 and prevents entry of oil, whichhas not been filtered, to the gap therebetween.

A base insertion portion 151 f is provided on an end portion of theaccommodation case 151 on the +X side in the axial direction. The baseinsertion portion 151 f functions as an attachment portion that isattached to the base (14 a in FIG. 3) of the housing and includes athrough-hole 151 f 1 and an attachment surface 151 f 2. The attachmentsurface 151 f 2 extends in the X-Y-axis direction. Although thethrough-hole 151 f 1 is provided in the attachment surface 151 f 2 andpenetrates through the accommodation case 151 in the Z-axis direction,the through-hole 151 f 1 does not communicate with the inside of theaccommodation case 151 since the through-hole 151 f 1 includes a tubularcircumferential wall. The attachment surface 151 f 2 of the baseinsertion portion 151 f is attached to the attachment catching surface14 a 1 of the base 14 a on the motor portion 10 illustrated in FIG. 3 ina close contact state.

In FIG. 3, two bolts 45 projecting toward the −Z side are provided onthe attachment catching surface 43 a of the suctioning-side flange 43 onthe pump portion 40. The two bolts are caused to pass through thethrough-holes 151 d in the accommodation case 151 of the filter module150.

A bolt 15 projecting toward the −Z side is provided in the attachmentcatching surface 14 a 1 of the base 14 a. The bolt 15 is caused to passthrough the through-hole 151 f 1 of the base insertion portion 151 f atthe filter module 150.

The bolts 45 caused to pass through the two through-holes 151 d in theaccommodation case of the filter module 150 and the bolt 15 caused topass through the through-hole 151 f 1 of the base insertion portion 151f are fastened with nuts 160. The filter module 150 is secured to themotor portion 10 and the pump portion 40 through the fastening. The thussecured filter module 150 causes the outlet port 151 c provided in theattachment surface 151 b to communicate with the suctioning port 41provided at the suctioning-side flange 43 illustrated in FIG. 3. Thebolts 45, the bolt 15, and the nuts 160 function as secure members asfollows. That is, the bolts 45, the bolt 15, and the nuts 160 aresecuring fasteners that secure the base insertion portion 151 f and theflange portion 151 b of the filter module 150 to the base 14 a and thesuctioning-side flange 43 in a posture in which the outlet port 151 c ofthe filter module 150 is caused to communicate with the suctioning port41 of the electric oil pump main body.

The securing fasteners are not limited to the bolts and the nuts. Forexample, a combination of female screw holes and male screws may also beemployed. Alternatively, rivets, caulking members, welded members, orthe like may also be employed.

The filter module 150 secured to the electric oil pump main body causesan internal space of the accommodation case 151 and the suctioning port41 provided at the suctioning-side flange 43 illustrated in FIG. 3 tocommunicate with each other. The two through-holes 151 d of the filtermodule 150 illustrated in FIG. 4 penetrate from the end surface of theaccommodation case 151 on the +Z side to the end surface thereof on the−Z side in the Z-axis direction. The two through-holes 151 d includetubular circumferential walls and thus do not communicate with theinside of the accommodation case 151.

The filter module 150 secured to the motor portion 10 and the pumpportion 40 of the electric oil pump main body covers the suctioning port41 provided at the pump portion 40. If a suctioning force is generatedat the suctioning port 41, then the pressure in the internal space ofthe accommodation case 151 that communicates with the suctioning port 41via the outlet port (151 c in FIG. 4) of the accommodation case 151 ofthe filter module 150 becomes a negative pressure. Due to the negativepressure, a suctioning force is generated in the inlet port opening 151a of the accommodation case 151. Due to the suctioning force, the oilflows into the internal space of the accommodation case 151 through theinlet port opening 151 a.

As illustrated in FIG. 4, the oil filter 153 with a volume with whichthe internal space of the accommodation case 151 is substantially filledis accommodated in the accommodation case 151 of the filter module 150.The oil filter 153 filters the oil with a finer mesh than a metal meshthat is typically used to remove impurities. The oil filter 153 is madeof a filter material such as a filter paper folded in a accordion shape,a non-woven cloth, or synthetic fiber solidified in a sponge form, orthe like.

Unlike the electric oil pump device 1 according to the exampleembodiment, it is necessary to use a member made of metal with highrigidity, such as a metal mesh, as a filter material in theconfiguration in which the suctioning port 41 is covered with the filtermaterial attached directly to the suctioning-side flange 43 illustratedin FIG. 3. Since the fineness of the mesh of the filter material made ofmetal is limited due to a difficulty in metal working, it is difficultto remove fine impurities such as metal powder. Meanwhile, in the moduleprovided with the accommodation case 151 for accommodating the oilfilter 153 as a filter material as in the electric oil pump device 1according to the example embodiment, it is possible to use a filtermaterial with a fine mesh made of a filter paper, a non-woven cloth, asynthetic fiber, or the like. Accordingly, it is possible tosatisfactorily remove fine impurities such as metal powder from the oilaccording to the electric oil pump device 1.

The oil that has flow into the internal space of the accommodation case151 moves from the −Z side to the +Z side in the Z-axis direction due tothe suctioning force generated by the suctioning port 41 of the pumpportion 40 illustrated in FIG. 3. By the oil passing through the oilfilter 153 illustrated in FIG. 4 in the process of the movement,particles that are finer than the mesh of a screen 152 are removed fromthe oil. The oil, from which the fine impurities have been removed, issuctioned into the pump portion 40 via the outlet port 151 c of theaccommodation case 151 and the suctioning port 41 of the pump portion 40illustrated in FIG. 3.

A surface of the accommodation case 151, in which the inlet port opening151 a is provided, extends in the X-Y plane direction. In the plane, anopening area of the inlet port opening 151 a is larger than an area of aportion except for the inlet port opening 151 a. With such aconfiguration, the oil moves to the +Z side along the Z-axis directionwhile satisfactorily spreading in the X-Y plane direction in the oilfilter 153. Therefore, it is possible to curb a decrease in lifetime ofthe oil filter 153 due to acceleration of clogging of a specific regionas compared with clogging of the other regions caused because of thepassing oil concentrating on the specific region in the X-Y planedirection of the oil filter 153.

<Effects and Advantages of Electric Oil Pump Device 1>

(1) The electric oil pump device 1 includes the filter module 150including the inlet port opening 151 a that serves as an inlet port forreceiving oil, an outlet port 151 c that discharges the oil passingthrough the inlet port opening 151 a, and a flange portion 151 b and thebase insertion portion 151 f that serve as an attachment portion. Also,the electric oil pump device 1 includes the suctioning-side flange 43and the base 14 a that serve as an attachment catching portion, which isprovided at the electric oil pump main body (including the motor portion10, the pump portion 40, and the like), to which the flange portion 151b and the base insertion portion 151 f of the filter module 150 areattached. Further, the electric oil pump device 1 includes the bolt 15,the bolts 45, and the nuts 160 as securing fasteners. The securingfasteners secure the flange portion 151 b and the base insertion portion151 f of the filter module 150 placed on the electric oil pump main bodyto the suctioning-side flange 43 and the base 14 a in a posture in whichthe outlet port 151 c is caused to communicate with the suctioning port41.

In the electric oil pump device 1 with such a configuration, it is notnecessary to secure a long and thin tubular installation space insidethe oil pan since the filter module 150 is attached directly to theelectric oil pump main body without the long and thin tubular portion(pipe) being interposed therebetween. Accordingly, it is possible tosave space and to reduce the weight of the oil pan. Further, it is alsopossible to reduce the number of components and to reduce costscorresponding to the unnecessary long and thin tubular portion.

Also, since it is possible to attach the electric oil pump device 1 in astate in which the filter module 150 is attached to the electric oilpump main body to the oil pan according to the electric oil pump device1, it is not necessary to align the suctioning port 41 of the electricoil pump main body and the outlet port 151 c of the filter module 150 inthe oil pan. Therefore, it is possible to improve mountability of thefilter module 150 and the electric oil pump main body to the oil panaccording to the electric oil pump device 1.

Also, the oil, from which the impurities have been removed with thefilter module 150, is caused to flow into the suctioning port 41 of theelectric oil pump main body without passing through the long and thintubular portion according to the electric oil pump device 1. Therefore,it is possible to improve pump efficiency of the electric oil pump mainbody according to the electric oil pump device 1.

(2) In the electric oil pump device 1, the filter module 150 includesthe oil filter 153 that filters the oil and the accommodation case 151that accommodates the oil filter 153. The inlet port opening 151 a asthe inlet, the outlet port 151 c, and the flange portion 151 b and thebase insertion portion 151 f that serve as attachment portions areprovided at the accommodation case 151.

In the electric oil pump device 1 with such a configuration, it ispossible to use a material that has a finer mesh than a filter materialmade of metal such as a metal mesh and is made of a filter paper, anon-woven cloth, a synthetic fiber, or the like with rigidity that islower than that of metal can be used as the oil filter 153. Therefore,it is possible to satisfactorily remove fine impurities such as metalpowder with the filter module 150 according to the electric oil pumpdevice 1.

(3) In the electric oil pump device 1, the suctioning port 41 isdirected in the radial direction (Z-axis direction) around the centralaxial line of the motor shaft (shaft 13) of the motor portion 10. Theflange portion 151 b and the base insertion portion 151 f that serve asattachment portions include an attachment surface 151 b that is attachedto the side of the pump portion 40 and the attachment surface 151 f 2that is attached to the side of the motor portion 10. The filter module150 is secured to the electric oil pump main body in a form in which thefilter module 150 faces both the pump portion 40 and the motor portion10 in the axial direction as illustrated in FIG. 1.

In the electric oil pump device 1 with such a configuration, the filtermodule 150 faces both the pump portion 40 and the motor portion 10 andhas an enlarged size due to a shape extending in the axial direction.According to the electric oil pump device 1, it is possible to extendthe lifetime of the oil filter 153 by enlarging the size of the oilfilter 153 as described above.

Next, the respective example embodiments achieved by adding furtherconfigurations to the electric oil pump device 1 according to theexample embodiment will be described. Note that the configuration of theelectric oil pump device 1 in the respective example embodiments issimilar to that in the aforementioned example embodiment unlessparticularly indicated otherwise.

[First Example Embodiment]

FIG. 5 is a plan view illustrating the electric oil pump device 1 fromthe −Z side in the Z-axis direction according to a first exampleembodiment in a state in which the external pipe (202 in FIG. 3) and thefilter module (150 in FIG. 3) have been removed therefrom. Asillustrated in the drawing, the suctioning port 41 is provided so as tobe closer to the motor portion 10 than the ejection port 42 is in theaxial direction along the X axis in the electric oil pump deviceaccording to the first example embodiment. The suctioning port 41 andthe ejection port 42 are aligned on the axial line extending in theaxial direction represented by the one-dotted dashed line in FIG. 5.

Two bolts 161 are provided in an end surface of the ejection-side flange44 on the −Z side in the Z-axis direction. The two bolts 161 projecttoward the −Z side from the aforementioned end surface.

FIG. 6 is a plan view illustrating the electric oil pump device 1 fromthe −Z side in the Z-axis direction according to the first exampleembodiment in a state in which the external pipe 202 and the filtermodule 150 have been attached thereto. In the drawing, the bolts 161provided at the ejection-side flange (44 in FIG. 5) penetrate throughthe through-holes of the external flange 201. The external flange 201 isconnected to the ejection-side flange of the electric oil pump main bodyby the bolts 161 being fastened with nuts 160.

In FIG. 6, the Z-axis lines L1 are axial lines extending in the Z-axisdirection and passing through the nuts 160. The external pipe 202connected to the external flange 201 extends on the +X side (the side ofthe filter module 150) in the axial direction, is then bent on the −Yside, extends in the Y-axis direction, is further bent on the +X side,and extends in the axial direction so as not to overlap with the Z-axislines L1 in the X-Y plane.

By the external pipe 202 extending on the +X side so as not to overlapwith the Z-axis lines L1 near the portion of connection to the externalflange 201, it is possible to easily fit a tool into nuts 160 withoutallowing the external pipe 202 to buffer in the Z-axis direction, asillustrated in FIG. 6. In this manner, the operation of fastening thenuts 160 is facilitated, and operability of attaching the externalflange 201 to the ejection-side flange (44 in FIG. 5) is thus improved.

Also, the external pipe 202 extending on the +X side, being bent on the−Y side, and being further bent on the +X side near the portion ofconnection to the external flange 201 enables the following matter. Thatis, it is possible to connect the external pipe 202 to a pipe on thevehicle side even in a layout in which a connection position of the pipeon the vehicle side for the external pipe 202 is present so as to becloser to the motor portion 10 (+X side) than the suctioning port (41 inFIG. 5) is.

<Effects and Advantages of the Electric Oil Pump Device 1 According toFirst Example Embodiment>

(4) In the electric oil pump device 1, the suctioning port 41 isprovided so as to be closer to the motor portion 10 than the ejectionport 42 is in the axial direction along the X axis as illustrated inFIG. 5.

In the electric oil pump device 1 with such a configuration, it ispossible to employ a layout in which the ejection port 42 of the pumpportion 40 is not interposed between the accommodation case 151 of thefilter module 150 and the suctioning port 41 of the pump portion 40 inthe axial direction as illustrated in FIG. 3. According to the electricoil pump device 1 that employs such a layout, an operator can easilyattach and detach the external pipe 202 on the ejection side that isconnected to the ejection port 42 of the pump portion 40 to and from thepump portion 40 without being interrupted by the accommodation case 151of the filter module 150.

Also, in the electric oil pump device 1, the filter module 150 attachedto the suctioning-side flange 43 provided with the suctioning port 41 ispresent so as to be closer to the motor portion 10 than the ejectionport 42, since the suctioning port 41 being present so as to be closerto the motor portion 10 than the ejection port 42 is in the axialdirection. Therefore, the filter module 150 does not project in theaxial direction beyond the electric oil pump main body including themotor portion 10, the pump portion 40, and the like as illustrated inFIG. 3. Therefore, according to the electric oil pump device 1, it ispossible to reduce the size of the electric oil pump device 1 in theaxial direction.

Also, in the electric oil pump device 1, the suctioning port 41 and theejection port 42 are aligned on the axial line extending in the axialdirection as illustrated in FIG. 5. In this manner, the position ofconnection between the suctioning port 41 and the filter module 150 andthe position of connection between the ejection port 42 and the externalpipe 202 for ejection are aligned in the axial direction. According tothe electric oil pump device 1 with such a configuration, it is possibleto prevent an increase in size of the electric oil pump device 1 causedby either one of the positions of connection deviating in the Y-axisdirection as compared with the other and the flange for connectionprojecting in the Y-axis direction beyond the outer diameter of theelectric oil pump main body.

[Second Example Embodiment]

FIG. 7 is an exploded side view illustrating the electric oil pumpdevice 1 according to the second example embodiment from the +Y side.The inverter 100 is secured to an end surface of the motor portion 10 onthe side (rear side) opposite to the side of the pump portion 40 in theaxial direction in a posture in which the longitudinal direction thereoffollows the Z-axis direction that is also a radial direction and an endportion in the longitudinal direction is caused to project beyond theend of the inverter of the electric oil pump main body in thelongitudinal direction. The filter module 150 is disposed in a region(step difference S) between the end of the inverter 100 in thelongitudinal direction and the end of the inverter of the electric oilpump main body in the longitudinal direction.

Typically, the diameter of the electric oil pump main body including thepump portion 40 and the motor portion 10 is smaller than the length ofthe inverter 100 in the longitudinal direction as illustrated in FIG. 7.Therefore, in the electric oil pump device 1 in which the inverter 100is secured to the motor portion 10 in the aforementioned posture, thestep difference S is generated between an end point P of the inverter100 and end points of the pump portion 40 and the motor portion 10 inthe radial direction, and the step difference S is likely to become adead space.

<Effects and Advantages of the Electric Oil Pump Device 1 According toSecond Example Embodiment>

In the electric oil pump device 1, the inverter 100 is secured to theend surface on the side opposite to the side of the pump portion 40 inthe axial direction. The posture of the inverter 100 secured to the endsurface is a posture as follows. That is, the posture of the inverter100 is a posture in which the longitudinal direction of the inverter 100follows the radial direction, and the end portion of the inverter 100 inthe longitudinal direction is caused to project beyond the end of theelectric oil pump main body in the direction along the longitudinaldirection of the inverter 100 secured to the pump portion 40. The filtermodule 100 is disposed in a region (step difference S) between the endof the electric oil pump main body and the end of the end portion of theinverter 100 in the longitudinal direction.

According to the electric oil pump device 1 with such a configuration,it is possible to effectively utilize a dead space and to save spacesince the filter module 150 is disposed in the step difference S.

[Third Example Embodiment]

FIG. 8 is a perspective view illustrating the filter module 150 of theelectric oil pump device 1 according to a third example embodiment. Thefilter module 150 includes a screen 152 made of a metal mesh secured tothe accommodation case 151. The screen 152 covers the inlet port opening151 a of the accommodation case 151. The mesh of the screen 152 isrougher than the mesh of the oil filter (153 in FIG. 4) in theaccommodation case 151.

In the electric oil pump device 1 with such a configuration, roughsolids in the oil are captured with the screen 152 with a mesh that isrougher than that of the oil filter 153 before capturing fine impuritiesfrom the oil with the oil filter 153 of the filter module 150.Therefore, according to the electric oil pump device 1, it is possibleto prevent a decrease in lifetime of the oil filter 153 due to cloggingof rough solids.

Although example embodiments of the present disclosure have beendescribed above, the disclosure is not limited to these exampleembodiments, and various modifications and changes can be made withinthe scope of the gist. These example embodiments and modificationsthereof are included in the scope and the gist of the disclosure and arealso included in the disclosure described in the claims and a rangeequivalent thereto.

While example embodiments of the present disclosure have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing from the scopeand spirit of the present disclosure. The scope of the presentdisclosure, therefore, is to be determined solely by the followingclaims.

What is claimed is:
 1. An electric oil pump device, comprising: anelectric oil pump main body including a pump, a motor that drives thepump, a suction port that suctions oil, and an ejection port that ejectsthe oil; a filter module that includes an inlet port that receives theoil, an outlet port that discharges the oil passing through the inletport, and an attachment that is attached to the electric oil pump mainbody; an attachment catch, which is provided on the electric oil pumpmain body, to which the attachment of the filter module is attached; anda fastener that secures, to the attachment catch, the attachment of thefilter module placed on the attachment catch of the electric oil pumpmain body in a posture in which the outlet port is caused to communicatewith the suction port of the electric oil pump main body.
 2. Theelectric oil pump device according to claim 1, wherein the filter moduleincludes a filter that filters the oil and an accommodation case thataccommodates the filter; and the inlet port, the outlet port, and theattachment are provided on the accommodation case.
 3. The electric oilpump device according to claim 2, wherein the suction port is directedin a direction around a central axial line of a motor shaft of themotor; the attachment includes a first attachment surface that isattached to a side of the pump and a second attachment surface that isattached to a side of the motor; and the filter module is secured to theelectric oil pump main body such that the filter module opposes both thepump and the motor in an axial direction.
 4. The electric oil pumpdevice according to claim 3, wherein the suction port is closer to themotor than the ejection port in the axial direction; and the suctionport and the ejection port are aligned along an axial line extending inthe axial direction.
 5. The electric oil pump device according to claim3, wherein an inverter that controls driving of the motor is secured toan end surface of the motor on a side opposite to a side of the pump inthe axial direction; a posture of the inverter secured to the endsurface is a posture in which a longitudinal direction of the inverterfollows the radial direction and an end portion of the inverter in thelongitudinal direction projects beyond an end of the electric oil pumpmain body in a direction along the longitudinal direction of theinverter secured to the pump; and the filter module is in a regionbetween the end of the electric oil pump main body and an end of the endportion of the inverter in the longitudinal direction.
 6. The electricoil pump device according to claim 4, wherein an inverter that controlsdriving of the motor is secured to an end surface of the motor on a sideopposite to a side of the pump in the axial direction; a posture of theinverter secured to the end surface is a posture in which a longitudinaldirection of the inverter follows the radial direction and an endportion of the inverter in the longitudinal direction projects beyond anend of the electric oil pump main body in a direction along thelongitudinal direction of the inverter secured to the pump; and thefilter module is in a region between the end of the electric oil pumpmain body and an end of the end portion of the inverter in thelongitudinal direction.